Can’t start your Mazda due to a faulty crankshaft position sensor? Learn how to fix it by following the procedures below.
A problem that may cause no-start problems on a Mazda or lead to the engine running rough is a failed crankshaft position sensor. A Mazda crankshaft position sensor (CPS) monitors the position and rotation speed of the crankshaft.
Common symptoms of a bad Mazda crankshaft position sensor include:
- Mazda won’t start
- Intermittent Starting
- Check Engine Light On
- Mazda cranks but won’t start.
- Engine idles rough
- Fault Codes: P0335, P0017, P0016
These symptoms may be intermittent in some cases. That’s why diagnosing a bad crankshaft position sensor makes it hard, especially if the check engine light has not turned on.
Follow these steps to change the crankshaft position sensor on a Mazda.
You will need
- Mazda Crankshaft Position Sensor
- Jack Stands
- Vehicle Jack
- Mechanic Toolset Metric
- Park your Mazda on level ground. Engage parking brakes. Let the engine cool down.
- Jack up the front right (passenger) side wheel. The CPS sensor is located on the same side where you have the serpentine belt. It is not on the transmission side.
- Remove the front wheel. Secure your vehicle with a good set of jack stands and block a tire so your car doesn’t roll.
- Remove the plastic wheel well liner. It is held with several plastic clips, 8mm or 10 mm nuts, depending on the Mazda model.
- Locate the crankshaft position sensor.
- Unplug the electrical connector.
- Remove two 8mm bolts.
- Before removing the old crankshaft position sensor, mark the old sensor’s exact position with a marker. You need to install the new CPS sensor in the same location.
- Install a new crankshaft position sensor on your Mazda engine block. Notice that the mounting holes are not round but oval. This allows the sensor to be moved slightly.
- Before you tighten the screws, make sure that the new sensor is in the same location as the old one.
- Use the bolt in the crankshaft center to turn the engine until cylinder 1 hits Top Dead Center (TDC) on the compression stroke.
- You will need to align the fifth tooth to the center of the sensor magnetic tip.
- Check with your Mazda dealer, as these instructions may vary between different 2.0, 2.3, and 2.5 Mazda engine sizes.
If the crank sensor fails on your Mazda, your car will refuse to start intermittently.
- If your Mazda is not starting, it is possible that the fuel pump has failed or is not generating enough pressure.
- Spark plugs and ignition coils can also be effective and could be another reason your Mazda does not start.
Check Engine Still On
If the check engine light is still on after replacing the crankshaft position sensor, you can use the YOUCANIC Full System Scanner to clear the stored codes on your vehicle. This scanner can also read and clear fault codes on every control module of the Mazda vehicle.